Conductor roll assembly for electrolytic strip tinning

ABSTRACT

A conductor roll assembly includes a roll body having aligned shaft sections extending outwardly from the roll body, one at each end thereof. A copper or other high electrical conducting material is applied over the roll body and over a portion of the shaft sections. A cylindrical seat and cylindrical bearing journal are provided on the copper of each roll section with the seat spaced outwardly from the journal. A split bearing surrounding each bearing journal rotatably supports the roll. A collector ring is mounted on each seat and welded to the shaft. The axis of the ring opening is offset with respect to the axis of its cylindrical body with the minimum thickness of one ring in alignment with the maximum thickness of the other so that the roll is substantially dynamically balanced.

nited States Patent .1191

Paradine CONDUCTOR ROLL ASSEMBLY FOR ELECTROLYTIC STRIP TINNING [75]Inventor: Terry E. Paradine, Gary, Ind.

[73] Assignee: United States Steel Corporation, Pittsburgh, Pa.

22 Filed: Feb. 25, 1972 211 Appl. No.: 229,472

[52] U.S. Cl. 191/1 A, 204/25, 339/5 [51] int. Cl B01k 3/02 [58] Fieldof Search 310/219, 231, 232; 191/1 A; 74/573; 339/5 R; 204/25;

[56] References Cited UNITED STATES PATENTS 1,918,627 7 1933 Ballard 20425 2,451,872 10/1948 Rodgers 310/232 x Willingham 191/1 A 14 1 Oct.1,1974 Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-George H.Libman Attorney, Agent, or Firm-Arthur J. Greif 57 ABSTRACT A conductorroll assembly includes a roll body having aligned shaft sectionsextending outwardly from the roll body, one at each end thereof. Acopper or other high electrical conducting material is applied over theroll body and over a portion of the shaft sections. A

cylindrical seat and cylindrical bearing journal are provided on thecopper of each roll section with the seat spaced outwardly from thejournal. A split hearing surrounding each bearing journal rotatablysupports the roll. A collector ring is mounted on each seat and weldedto the shaft. The axis of the ring opening is offset with respect to theaxis of its cylindrical body with the minimum thickness of one ring inalignment with the maximum thickness of the other so that th roll issubstantially dynamically balanced.

2 Claims, 2 Drawing Figures (Minimum nan I N\ NN H CONDUCTOR RoLLASSEMBLY FOR ELECTROLYTIC STRIP TINNING This invention relates to aconductor roll assembly and more particularly to such an assembly foruse in high speed electrolytic strip tinning lines. These lines travelat speeds up to 1,800 ft. per minute and generally travel at speeds ofat least 1,000 ft. per minute. The electric power applied to the rollshas a low voltage (12 to 30 volts) and a high current which may be asmuch as 20,000 amperes and generally is at least 10,000 amperes. Theface of rolls commonly used is in the neighborhood of 46 inches wide.The rolls which the rolls of my invention are replacing include a rollbody with a shaft section at each end having a tapered portion with acollector ring having a matching tapered opening mounted thereon andsecured thereto by means of a nut threaded on the shaft. The axis of thecollector ring opening is offset with respect to the outer surface ofthe ring to provide eccentricity which prevents sticking of the brusheswhich contact the outer periphery of the collector rings. The roll isrotated on bearings located between the roll body and collector rings.This general type of conductor roll assemblies have been in use for over30 years. The present cost of such rolls is approximately $8,000.00 andafter approximately 3 to 4 months service they must be removed andrepaired at a cost of approximately $4,000.00. Many problems are presentin the use of this type of roll. The electrical contact between the ringand shaft is not too good and gets worse as time passes. Damage to thebearings occur, thus requiring frequent replacement. The nuts have to betightened frequently and maintenance costs are high. 1 have found that agreat deal of the difficulty arises because the roll is not dynamicallybalanced since no attempt has been made to position the collector ringswith the thick portion of one aligned with the thin portion of theother. and because the tapered portions on the shaft and collector ringare seldom closely matched.

It is therefore an object of my invention to provide a conductor rollassembly which has substantially greater life than previous rollassemblies.

Another object is to provide such an assembly which has betterconductivity betweenlhe collector rings and the roll surface.

Still another object is to provide such an assembly which requireslittle maintenance. I

A further object is to provide such an assembly which has increasedbearing .life.

These and other objects will be more apparent after referring to the"following specification and attached drawings, in which:

FIG. 1 is a sectional view, partly in elevation, of the assembly of myinvention; and

FIG. 2 is a view taken on the line 11-11 of FIG. 1.

Referring more particularly to the drawings, reference numeral 2indicates a conductor roll having a roll body 4 mounted on a shaft 6extending from each end of the roll body. The body 4 includes a mainsteel portion 8 and an outer layer 10 made of a high electricalconducting material such as copper or aluminum bronze. The layers 10also extend over the sides of the roll body and around each end sectionof the shaft. A thin coating of chromium or the like (.not shown) isapplied to the outer surface of layer 10. The parts so far -that thering has a maximum thickness 22 described exce t for the shape of theouter sections of the shaft are 0 d.

Accordingto my invention 1 provide a cylindrical seat 12 on the layer 10of each end section of shaft 6 and a cylindrical bearing journal 14coaxial with seat 12 and located between seat 12 and the roll body 4. Acollector ring 16 made of high conductive material such as copper or thelike is mounted on each seat 12. Like the rings of the prior art thematerial of ring 16 is harder than the layer 10. The outer periphery 18of the n h fi is... y .i.nd. l b ts a i pff (P r l/32 inch) with respectto the axis of its opening 20 so spaced approximately from its minimumthickness 24 as best shown in FIG. 2. Welds or solder 26 are providedbetween the sides of collector ring 16 and the shaft adjacent thereto.As used hereinafter the term welds includes both welds and solder. Themaximum thickness portion 22 of one ring is positioned in generalalignment with the minimum thickness portion 24 of the other ring 16.The rolls are mounted in split bearings 28 which are preferably a Coopersplit bearing No. EX MC 508 which is distributed by Berry BearingCompany of Chicago, Illinois. The outer surfaces of rings 16 contactbrushes 30 in the usual manner.

The conductor roll assembly is made up in the following manner. The roll2 is made in'the usual manner. Collector rings 16 are provided havingthe diameter of their openings 20 essentially the same as or slightlyless than the diameter of seats 12. The rings 16 are pressed onto theseats 12 of shaft 6 by means of a 50 ton press with the rings beingaligned with the thick portion 22 of one in alignment with the thinportion 24 of the other. The rings are then welded to the shaft asshown. If the completed roll is not in dynamic balance it is balanced inany suitable-manner such as by adding and/or removing weld metal. Theroll with the rings attached are then mounted in split bearings 28 andthe brushes 30 positioned to contact the outer periphery of the rm s.

\%'hile one embodiment of my invention has been shown and described, itwill be apparent that other adaptations and modifications may be madewithout departing from the scope of the following claims.

I claim:

1. In a conductor roll assembly which includes a cylindrical roll body,mounted on aligned shaft sections extending outwardly from said rollbody, one at each end thereof, said roll body and shaft sections havingan outer layer composed of a metal with a high electrical conductivity,collector rings mounted so as to encircle and be in tight engagementwith a circumferential portion of each shaft section, means for securingeach collector ring to the outer layer of its respective shaft section,bearing brushes adapted to contact the outer peripheries of saidcollector rings and means-for rotatably supporting said assembly,

the improvement wherein each collector ring is weldably secured to saidouter layer of its respective shaft section so as to cause each ring andits respective shaft to operate as an integral unit, thereby ma-Lerially enhancing the service life of said roll assem- 2. The rollassembly of claim 1, wherein each said collector ring is eccentric withrespect to the axis of its respective shaft, so that each ring has amaximum thickness spaced 180 from its minimum thickness, the

ring on one shaft section positioned so that its maximum thickness is ingeneral alignment with the minimum thickness of the ring on the othershaft section.

1. In a conductor roll assembly which includes a cylindrical roll body,mounted on aligned shaft sections extending outwardly from said rollbody, one at each end thereof, said roll body and shaft sections havingan outer layer composed of a metal with a high electrical conductivity,collector rings mounted so as to encircle and be in tight engagementwith a circumferential portion of each shaft section, means for securingeach collector ring to the outer layer of its respective shaft section,bearing brushes adapted to contact the outer peripheries of saidcollector rings and means for rotatably supporting said assembly, theimprovement wherein each collector ring is weldably secured to saidouter layer of its respective shaft section so as to cause each ring andits respective shaft to operate as an integral unit, thereby materiallyenhancing the service life of said roll assembly.
 2. The roll assemblyof claim 1, wherein each said collector ring is eCcentric with respectto the axis of its respective shaft, so that each ring has a maximumthickness spaced 180* from its minimum thickness, the ring on one shaftsection positioned so that its maximum thickness is in general alignmentwith the minimum thickness of the ring on the other shaft section.